Bobbi Kristina Brown's aunt Leolah Brown, in a new Facebook Post, vowed to get justice for her niece and Whitney Houston. Photo: Reuters

Bobbi Kristina Brown’s aunt, Leolah Brown, vowed in a Facebook post Friday that she will not let the deaths of her niece and Whitney Houston go “in vain.” Leolah has been vocal since her niece’s hospitalization in January, blaming the Houstons for her condition.

“Its been a tough trial & journey for me. However, it has just begun! But as always -- I'm keeping my faith in God! And I will make sure that my sister Whitney Houston Brown and my niece Bobbi Kristina Brown has not left us in vain! HANG IN THERE WITH ME," Leolah wrote.

Bobbi Kristina died on July 26 at the age of 22 after being in an unresponsive state for nearly six months. She was hospitalized and put in a medically induced coma after she was found facedown in a bathtub at her Atlanta home on Jan. 31. Her Grammy Award-winning mother Whitney died in 2012 after being found in similar circumstances at a hotel in Beverly Hills, Los Angeles.

Leolah’s comments come amid reports that Bobbi Kristina’s boyfriend Nick Gordon may have cheated on the aspiring actress. Rumors swirled that Gordon was dating Bobbi Kristina’s friend Danyela Bradley. The allegation comes after Gordon was photographed smiling and pushing Bradley in a wheelchair out of North Fulton Hospital in Atlanta, a day after Bobbi Kristina was admitted to the hospital.

Bradley is also reportedly believed to be the “white girl” named in an amended civil lawsuit filed against Gordon by Bedelia Hargrove, Bobbi Kristina’s legal conservator. The suit claims that the girl heard Gordon abuse Bobbi Kristina, moments before the tragic incident. It also alleges that Gordon drugged Bobbi Kristina with a “toxic cocktail” and then drowned her in the bathtub. He is also accused of abusing his girlfriend and stealing her money.

A preliminary autopsy on Bobbi Kristina showed no significant injuries or obvious cause of death. However, police are treating her case as a homicide.